From patchwork Fri Apr 5 02:46:34 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 13618401 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A6FE9CD1284 for ; Fri, 5 Apr 2024 02:47:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=U3v8OMLbHJQe3uj8mAF4n1iofgwFgBXDTrtxgYYA4Ow=; b=RlMcNn0QCuf/aH nkxzt74TwGoLob7Yv3QI6bpTKyQ7fJUs5DWVMqaAE0H/wrrq4xxrMiejYGMyOMUlmJpzi6Oolcgds xa8h2aJFReo0ui2WkFASlRieBkwwBSWXR+2JVD/nDCYBhBs9yS4/p0S85DG+UJQw2zTJKlROJ4xZB nnrOhhhuwfrihgjW0BPpRMhOyjKllZa/8XMToHW0iHmq9UkrM1dGKfZZI161LxjiDko25GVMepCYk XO7DVflvqYuV6vOT2z6ooMNkrikewS2qjnFJdjCcC/Dj/ofVxyyTWhpZ3Yd+EwHXAZWbOLwAI4JNB t4jxiQWB8+o9k/4D/4jA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rsZc0-00000004wTW-0wmE; Fri, 05 Apr 2024 02:47:28 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rsZbs-00000004wOG-2SgI for linux-arm-kernel@lists.infradead.org; Fri, 05 Apr 2024 02:47:26 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 64B6BFEC; Thu, 4 Apr 2024 19:47:50 -0700 (PDT) Received: from a077893.blr.arm.com (a077893.blr.arm.com [10.162.41.6]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 28F0E3F766; Thu, 4 Apr 2024 19:47:13 -0700 (PDT) From: Anshuman Khandual To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, will@kernel.org, catalin.marinas@arm.com, mark.rutland@arm.com Cc: Anshuman Khandual , Mark Brown , James Clark , Rob Herring , Marc Zyngier , Suzuki Poulose , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , linux-perf-users@vger.kernel.org, Jonathan Corbet , Oliver Upton , linux-doc@vger.kernel.org Subject: [PATCH V17 4/9] arm64/boot: Enable EL2 requirements for BRBE Date: Fri, 5 Apr 2024 08:16:34 +0530 Message-Id: <20240405024639.1179064-5-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240405024639.1179064-1-anshuman.khandual@arm.com> References: <20240405024639.1179064-1-anshuman.khandual@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240404_194720_944579_115C1ABD X-CRM114-Status: GOOD ( 18.05 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Fine grained trap control for BRBE registers, and instructions access need to be configured in HDFGRTR_EL2, HDFGWTR_EL2 and HFGITR_EL2 registers when kernel enters at EL1 but EL2 is present. This changes __init_el2_fgt() as required. Similarly cycle and mis-prediction capture need to be enabled in BRBCR_EL1 and BRBCR_EL2 when the kernel enters either into EL1 or EL2. This adds new __init_el2_brbe() to achieve this objective. This also updates Documentation/arch/arm64/booting.rst with all the above EL2 along with MDRC_EL3.SBRBE requirements. First this replaces an existing hard encoding (1 << 62) with corresponding applicable macro HDFGRTR_EL2_nPMSNEVFR_EL1_MASK. Cc: Catalin Marinas Cc: Will Deacon Cc: Jonathan Corbet Cc: Marc Zyngier Cc: Oliver Upton Cc: linux-arm-kernel@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual ---- Changes in V17: - New patch added in the series - Separated out from the BRBE driver implementation patch - Dropped the comment in __init_el2_brbe() - Updated __init_el2_brbe() with BRBCR_EL2.MPRED requirements - Updated __init_el2_brbe() with __check_hvhe() constructs - Updated booting.rst regarding MPRED, MDCR_EL3 and fine grained control Documentation/arch/arm64/booting.rst | 26 ++++++++ arch/arm64/include/asm/el2_setup.h | 90 +++++++++++++++++++++++++++- 2 files changed, 113 insertions(+), 3 deletions(-) diff --git a/Documentation/arch/arm64/booting.rst b/Documentation/arch/arm64/booting.rst index b57776a68f15..512210da7dd2 100644 --- a/Documentation/arch/arm64/booting.rst +++ b/Documentation/arch/arm64/booting.rst @@ -349,6 +349,32 @@ Before jumping into the kernel, the following conditions must be met: - HWFGWTR_EL2.nSMPRI_EL1 (bit 54) must be initialised to 0b01. + For CPUs with feature Branch Record Buffer Extension (FEAT_BRBE): + + - If the kernel is entered at EL2 and EL1 is present: + + - BRBCR_EL1.CC (bit 3) must be initialised to 0b1. + - BRBCR_EL1.MPRED (bit 4) must be initialised to 0b1. + + - If the kernel is entered at EL1 and EL2 is present: + + - BRBCR_EL2.CC (bit 3) must be initialised to 0b1. + - BRBCR_EL2.MPRED (bit 4) must be initialised to 0b1. + + - HDFGRTR_EL2.nBRBDATA (bit 61) must be initialised to 0b1. + - HDFGRTR_EL2.nBRBCTL (bit 60) must be initialised to 0b1. + - HDFGRTR_EL2.nBRBIDR (bit 59) must be initialised to 0b1. + + - HDFGWTR_EL2.nBRBDATA (bit 61) must be initialised to 0b1. + - HDFGWTR_EL2.nBRBCTL (bit 60) must be initialised to 0b1. + + - HFGITR_EL2.nBRBIALL (bit 56) must be initialised to 0b1. + - HFGITR_EL2.nBRBINJ (bit 55) must be initialised to 0b1. + + - If EL3 is present: + + - MDCR_EL3.SBRBE (bits 33:32) must be initialised to 0b11. + For CPUs with the Scalable Matrix Extension FA64 feature (FEAT_SME_FA64): - If EL3 is present: diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h index b7afaa026842..7c12a8e658d4 100644 --- a/arch/arm64/include/asm/el2_setup.h +++ b/arch/arm64/include/asm/el2_setup.h @@ -154,6 +154,41 @@ .Lskip_set_cptr_\@: .endm +#ifdef CONFIG_ARM64_BRBE +/* + * Enable BRBE cycle count and miss-prediction + * + * BRBE requires both BRBCR_EL1.CC and BRBCR_EL2.CC fields, be set + * for the cycle counts to be available in BRBINF_EL1.CC during + * branch record processing after a PMU interrupt. This enables CC + * field on both these registers while still executing inside EL2. + * + * BRBE driver would still be able to toggle branch records cycle + * count support via BRBCR_EL1.CC field regardless of whether the + * kernel ends up executing in EL1 or EL2. + * + * The same principle applies for branch record mis-prediction info + * as well, thus requiring MPRED field to be set on both BRBCR_EL1 + * and BRBCR_EL2 while still executing inside EL2. + */ +.macro __init_el2_brbe + mrs x1, id_aa64dfr0_el1 + ubfx x1, x1, #ID_AA64DFR0_EL1_BRBE_SHIFT, #4 + cbz x1, .Lskip_brbe_\@ + + mov_q x0, BRBCR_ELx_CC | BRBCR_ELx_MPRED + msr_s SYS_BRBCR_EL2, x0 + + __check_hvhe .Lset_brbe_nvhe_\@, x1 + msr_s SYS_BRBCR_EL12, x0 // VHE + b .Lskip_brbe_\@ + +.Lset_brbe_nvhe_\@: + msr_s SYS_BRBCR_EL1, x0 // NVHE +.Lskip_brbe_\@: +.endm +#endif /* CONFIG_ARM64_BRBE */ + /* Disable any fine grained traps */ .macro __init_el2_fgt mrs x1, id_aa64mmfr0_el1 @@ -161,16 +196,48 @@ cbz x1, .Lskip_fgt_\@ mov x0, xzr + mov x2, xzr mrs x1, id_aa64dfr0_el1 ubfx x1, x1, #ID_AA64DFR0_EL1_PMSVer_SHIFT, #4 cmp x1, #3 b.lt .Lset_debug_fgt_\@ + /* Disable PMSNEVFR_EL1 read and write traps */ - orr x0, x0, #(1 << 62) + orr x0, x0, #HDFGRTR_EL2_nPMSNEVFR_EL1_MASK + orr x2, x2, #HDFGWTR_EL2_nPMSNEVFR_EL1_MASK .Lset_debug_fgt_\@: +#ifdef CONFIG_ARM64_BRBE + mrs x1, id_aa64dfr0_el1 + ubfx x1, x1, #ID_AA64DFR0_EL1_BRBE_SHIFT, #4 + cbz x1, .Lskip_brbe_reg_fgt_\@ + + /* + * Disable read traps for the following registers + * + * [BRBSRC|BRBTGT|RBINF]_EL1 + * [BRBSRCINJ|BRBTGTINJ|BRBINFINJ|BRBTS]_EL1 + */ + orr x0, x0, #HDFGRTR_EL2_nBRBDATA_MASK + + /* + * Disable write traps for the following registers + * + * [BRBSRCINJ|BRBTGTINJ|BRBINFINJ|BRBTS]_EL1 + */ + orr x2, x2, #HDFGWTR_EL2_nBRBDATA_MASK + + /* Disable read and write traps for [BRBCR|BRBFCR]_EL1 */ + orr x0, x0, #HDFGRTR_EL2_nBRBCTL_MASK + orr x2, x2, #HDFGWTR_EL2_nBRBCTL_MASK + + /* Disable read traps for BRBIDR_EL1 */ + orr x0, x0, #HDFGRTR_EL2_nBRBIDR_MASK + +.Lskip_brbe_reg_fgt_\@: +#endif /* CONFIG_ARM64_BRBE */ msr_s SYS_HDFGRTR_EL2, x0 - msr_s SYS_HDFGWTR_EL2, x0 + msr_s SYS_HDFGWTR_EL2, x2 mov x0, xzr mrs x1, id_aa64pfr1_el1 @@ -193,7 +260,21 @@ .Lset_fgt_\@: msr_s SYS_HFGRTR_EL2, x0 msr_s SYS_HFGWTR_EL2, x0 - msr_s SYS_HFGITR_EL2, xzr + mov x0, xzr +#ifdef CONFIG_ARM64_BRBE + mrs x1, id_aa64dfr0_el1 + ubfx x1, x1, #ID_AA64DFR0_EL1_BRBE_SHIFT, #4 + cbz x1, .Lskip_brbe_insn_fgt_\@ + + /* Disable traps for BRBIALL instruction */ + orr x0, x0, #HFGITR_EL2_nBRBIALL_MASK + + /* Disable traps for BRBINJ instruction */ + orr x0, x0, #HFGITR_EL2_nBRBINJ_MASK + +.Lskip_brbe_insn_fgt_\@: +#endif /* CONFIG_ARM64_BRBE */ + msr_s SYS_HFGITR_EL2, x0 mrs x1, id_aa64pfr0_el1 // AMU traps UNDEF without AMU ubfx x1, x1, #ID_AA64PFR0_EL1_AMU_SHIFT, #4 @@ -228,6 +309,9 @@ __init_el2_nvhe_idregs __init_el2_cptr __init_el2_fgt +#ifdef CONFIG_ARM64_BRBE + __init_el2_brbe +#endif .endm #ifndef __KVM_NVHE_HYPERVISOR__